The present invention relates to a light radiator for effectively diffusing and radiating light rays, which have been transmitted through an optical conductor cable or the like out of of the optical conductor cable.
The present applicant has previously proposed various ways to focus solar rays or artificial light rays by use of lenses or the like, to guide the rays into an optical conductor cable, and thereby to transmit them onto an optional desired place through the optical conductor cable. The solar rays or the artificial light rays transmitted and emitted in such a way are employed for photo-synthesis, for use in illuminating, or for other like purposes, for example, to promote the cultivation of plants.
However, when utilizing light energy for cultivating plants as mentioned above, light rays transmitted through an optical conductor cable have directional characteristics. If the end portion of an optical conductor cable is cut off and light rays are emitted therefrom, the radiation angle for the focused light rays is, in general, equal to approximately 46.degree., which is quite narrow. When utilizing light energy as described above, it is impossible to attain a desirable amount of illumination simply by cutting off the end portion of an optical conductor cable and letting the light rays emit therefrom.
Therefore, the present applicant has already proposed various kinds of light radiators capable of effectively diffusing light rays which have been transmitted through an optical conductor cable and radiating them for illumination over a desired area.